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cat|dog|fishWord alternation: cat|dog|fishAlternationFormal RE✨ Emoji Combos

"cats" does NOT match — formal RE always tests the whole string. No substring search. Case-sensitive.

✓ Accepts

catdogfish

✗ Rejects

εcacatdogcatsCat

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Regular Expression Pattern

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Test String

Annotation

Unable to parse pattern

Active Flags:

gglobal: Don't return after first match

mmultiline: ^ and $ match start/end of each line

Match Results

0 matches

No matches found

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